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  <title>计算迭代器中元素的个数</title>
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  <div id="layout-content"><div id="function.iterator-count" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">iterator_count</h1>
  <p class="verinfo">(PHP 5 &gt;= 5.1.0, PHP 7, PHP 8)</p><p class="refpurpose"><span class="refname">iterator_count</span> &mdash; <span class="dc-title">计算迭代器中元素的个数</span></p>

 </div>

 <div class="refsect1 description" id="refsect1-function.iterator-count-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="methodname"><strong>iterator_count</strong></span>(<span class="methodparam"><span class="type"><span class="type"><a href="class.traversable.html" class="type Traversable">Traversable</a></span>|<span class="type">array</span></span> <code class="parameter">$iterator</code></span>): <span class="type">int</span></div>

  <p class="para rdfs-comment">
   对迭代器中的元素计数。<span class="function"><strong>iterator_count()</strong></span> 不能保留
   <code class="parameter">iterator</code> 的当前位置。
  </p>
 </div>


 <div class="refsect1 parameters" id="refsect1-function.iterator-count-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>
    
     <dt>
<code class="parameter">iterator</code></dt>

     <dd>

      <p class="para">
       要计数的迭代器。
      </p>
     </dd>

    
   </dl>

  </p>
 </div>


 <div class="refsect1 returnvalues" id="refsect1-function.iterator-count-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   <code class="parameter">iterator</code> 中的元素个数。
  </p>
 </div>


 <div class="refsect1 changelog" id="refsect1-function.iterator-count-changelog">
  <h3 class="title">更新日志</h3>
  <table class="doctable informaltable">
   
    <thead>
     <tr>
      <th>版本</th>
      <th>说明</th>
     </tr>

    </thead>

    <tbody class="tbody">
     <tr>
      <td>8.2.0</td>
      <td>
       <code class="parameter">iterator</code> 的类型从 <span class="type"><a href="class.traversable.html" class="type Traversable">Traversable</a></span>
       扩展为 <span class="type"><span class="type"><a href="class.traversable.html" class="type Traversable">Traversable</a></span>|<span class="type">array</span></span>。
      </td>
     </tr>

    </tbody>
   
  </table>

 </div>


 <div class="refsect1 examples" id="refsect1-function.iterator-count-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-3664">
    <p><strong>示例 #1 <span class="function"><strong>iterator_count()</strong></span> 示例</strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$iterator&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">ArrayIterator</span><span style="color: #007700">(array(</span><span style="color: #DD0000">'recipe'</span><span style="color: #007700">=&gt;</span><span style="color: #DD0000">'pancakes'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'egg'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'milk'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'flour'</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">iterator_count</span><span style="color: #007700">(</span><span style="color: #0000BB">$iterator</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
int(4)
</pre></div>
    </div>
   </div>
   <div class="example" id="example-3665">
    <p><strong>示例 #2 <span class="function"><strong>iterator_count()</strong></span> 修改位置</strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$iterator&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">ArrayIterator</span><span style="color: #007700">([</span><span style="color: #DD0000">'one'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'two'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'three'</span><span style="color: #007700">]);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$iterator</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">current</span><span style="color: #007700">());<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">iterator_count</span><span style="color: #007700">(</span><span style="color: #0000BB">$iterator</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$iterator</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">current</span><span style="color: #007700">());<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
string(3) &quot;one&quot;
int(3)
NULL
</pre></div>
    </div>
   </div>
   <div class="example" id="example-3666">
    <p><strong>示例 #3 <span class="function"><strong>iterator_count()</strong></span> 在 <a href="control-structures.foreach.html" class="link">foreach</a> 中循环</strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$iterator&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">ArrayIterator</span><span style="color: #007700">([</span><span style="color: #DD0000">'one'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'two'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'three'</span><span style="color: #007700">]);<br />foreach&nbsp;(</span><span style="color: #0000BB">$iterator&nbsp;</span><span style="color: #007700">as&nbsp;</span><span style="color: #0000BB">$key&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">$value</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"</span><span style="color: #0000BB">$key</span><span style="color: #DD0000">:&nbsp;</span><span style="color: #0000BB">$value</span><span style="color: #DD0000">&nbsp;("</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">iterator_count</span><span style="color: #007700">(</span><span style="color: #0000BB">$iterator</span><span style="color: #007700">),&nbsp;</span><span style="color: #DD0000">")\n"</span><span style="color: #007700">;<br />}</span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
0: one (3)
</pre></div>
    </div>
   </div>
  </p>
 </div>


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